Hair drying apparatus



March 16, 1943. c P s 2,314,101

HAIR DRYING APPARATUS Filed Dec. 10, 1937 2 Sheets-Sheet l March 16, 1943. Q pH Ps 2,314,101

HAIR DRY ING APPARATUS Filed Dec. 10, 1937 2 Sheets-Sheet 2 INVENTOR Patented Mar. 16, 1943 uru'riazn STATES- PATENT OFFICE HAIR DRYING APPARATUS Charles Albert Phipps, Hartsdale, N. Y. Application December 10, 1937, Serial No. 179,130

11 Claims.

This invention relates to an apparatus for drying hair on" the human head. It relates more specifically to the drying of womens hair with devices adapted for passing'air or other suitable gaseous drying vehicle over the head.

Oneof the objects of this invention is to provide an apparatus suitable for drying womens hair in a greatly decreased time'and with a minimum of discomfort to the subject.

Another object of this invention is to provide means for drying womens hair which permits continuously uniform operation and provides drying conditions which are independent of atmospheric weather conditions.

Another object of this invention-is to provide means for drying womens hair by the use of air of reduced moisture content and without danger of introducing chemical agents into contact with the hair or with the air being supplied thereto.

Another object of this invention is to reduce the time required for and the discomfort accompanying the drying of womens hair by passing air of reduced moisture content with such velocity and distribution to provide contact of turbulent air over the entire surface of the hair, thereby providing for rapid penetration of drying air to the scalp.

A further modification of this invention provides an improved apparatus for supplying air of reduced moisture content and of any temperature desired to meet the individual preference of the subject.

Another object of the invention is to provide means for drying womens hair to which has been applied liquids other than water, by which the vapors .of-"such liquids may be recovered, preferably while recirculating air over the head being dried.

This invention provides an apparatus by which it is possible to dry womens hair quickly with air which isno warmer, and may even be somewhat cooler, than the prevailing room temperature. The temperature of the air used may also be higher than that permissible when using damp air, without discomfort to the subject.

A further modification of this invention involves an improved apparatus having a central device for treating air and a distribution system cooperating therewith for supplying the treated air to a number of separate hair dryers, which may be individually controlled.

Other and further objects of this invention will be apparent from. the following description and the drawings herewith:

The drawings are-presented to illustrate suitable devices by which the process of the present invention may be carried out. These drawings are in diagrammatic form and the invention is not to be limited to the specific designs shown therein.

Referring to the drawings, Figure 1 is a diagrammatic illustration in sectional elevation of a device for drying womens hair with recirculated air which is chilled to condense moisture therefrom, provided with'elements for by-passing the refrigeration unit with a part of the recirculated air.

Figure 2 is a diagrammatic sketch in sectional elevation of a modification of the device shown in Figure l, for serving a plurality of drying hoods with a central refrigeration and heating system.

Figures 3 and 4 are diagrammatic sketches in sectional elevation of two types of refrigerating units suitable for use in the systems illustrated in Figures I and 2.

Figure 3 shows a refrigeration device of the type preferred for use when the chilling surfaces are maintained at temperatures at which there is little or no danger of ice formation.

Figure 4 shows a refrigeration device in which the chilling surfaces may be operated at temperatures sumciently low to cause frosting or ice formation.

Figures 5 to 8 present detailed illustrations of suitable air chilling tubes for use in the refrigeration units illustrated in Figures 3 and 4.

Figures 5 and 6 are diagrammatic sketches in sectional elevation and .plan, respectively, of an air chilling tube suitable for use in the refrigeration unit illustrated in Figure 3.

Figures 7 and 8 are diagrammatic sketches in sectional elevation and plan, respectively, of an air chilling tube suitable for use in the refrigeration unit illustrated in Figure 4.

Referring to the drawings in greater detail, air or other suitable gaseous drying medium is forced by a pump, compressor, or the like, such as the fan or blower I, by means of a tube or duct 2 through a cooling zone which may consist of a tank 3 containing cold heat-conductive fluid such as chilled brine. The direction or flow of the air through the cooling zone is preferably downwardly, so the water condensing from the air may be withdrawn from the cooling zone by gravity. The water condensing from the air in zone 2 is removed from the duct 4 by providing any suitable separation or withdrawal means, such as pipe 5 which may be provided with a trap 6 to permit automatic operation without leakage of air. If the hair to be dried has been wet with liquids other than water, the vapors of such liquids may also be condensed and withdrawn in the same manner as the water. Additional means for the recovery of such liquids may also be provided, such as adsorptive masses, active charcoal, gels, and the like, which may be placed in the air stream either before or after the chilling unit. Such adsorptive masses will preferably be placed in the path of the chilled air directly after it leaves the chilling and liquid separating zones in order to secure the increased efiiciency of the adsorbent at lower temperatures. The chilled air leaving the cooling zone is directed by duct 4 over heating surfaces indicated at l and 8. The heating unit I may be the hot coil of a refrigeration cycle used to chill the brine in tank 3. The heating unit 8 may be an auxiliary heater of any desired type, such as a steam or gas heated coil or an electrically heated element which is preferably controllable by the subject whose hair is being dried, or the operator, by means of suitable valves, switches, or rheostats 44.

The warm and dry air is then passed to any suitable device for directing it against the hair of the subject. This may be a hood of any conventional type or of the types illustrated at l9 and 29 in the drawings. These hoods are designed to provide uniform distribution of air over the head. While recirculation to the chilling device of the air is not necessary, it is usually preferred in order to reduce the refrigeration load and to avoid venting air into the room from the hood. The air leaving the hood i9 may be returned to the blower l by means of duct [0.

While the use of dry air in itself is a great advantage in decreasing the time required for drying a womans hair and in increasing the comfort of the subject, both of these advantages can be greatly enhanced by supplying the air in such volume and velocity that a highly tubulent flow of the air is obtained throughout the zone of contact with the hair. This causes the dry air to penetrate deeply towards the scalp and also increases the rate of drying due to its velocity. It also produces a cooling effect due to the increased rate of evaporation which permits the use of warmer dry air than would otherwise be possible without discomfort, again shortening the time that the subject must remain under the hood. The, maximum velocity permissible should, of course, be less than is capable of disarranging the hair, any velocity up to this limit being permissible.

It is also desirable. in providing for the comfort of the subject. to avoid escape of the warm air from the hood about her face and neck. This may be accomplished by maintaining a slightly sub-atmospheric pressure within the hood. Such reduced pressure may be provided in a closed recirculatory system by venting a small quantity of air from the high pressure zone, as by the vent II which may suitably be placed at or near the fan discharge, or at any part of the system where the pressure is greater than atmospheric.

The air cooling zone 2 may be chilled by any suitable means involving direct or indirect heat exchange. A preferred method is to use a refrigeration cycle of any of the conventional types having separate heat absorption and heat dissipation areas. For example only, and for convenience, the single refrigerant compression type condensation-evaporation cycle is illustrated in the drawings, although the invention may also be used with absorption type and with three component refrigeration systems such as the Electrolux cycle, or the like. For example, a suitable refrigerant may be compressed by compressor i2, condensed in heat dissipating coil I, passed by line l3 through expansion valve l4 into heat absorption coil l5, from which it is passed by line I8 back to the compressor.

There is further illustrated in Figure 1 a duct 20 through which air may by-pass the cooling and re-heating elements 2 and I. This duct is provided with a control valve or vane 2| for regulating the quantity of air permitted to pass therethrough. This by-pass valve preferably will not be opened until the moisture content of the air within the system is sufficiently low to permit the desired drying action, and it will preferably not be opened thereafter sufllciently to permit the moisture content of the air to the hood to exceed such amount. The use of the by-pass is advantageous in permitting recirculation of air at a high rate with a minimum load on the refrigeration unit. Also, in actual practice, the air leaving the hood l9 will not be saturated with moisture, and it will be generally sufllcient in continuous operation to pass only sufiicient air through the refrigerator to remove the increment of moisture picked up on each recirculation cycle.

Th air treating unit illustrated in Figure l is also designed to provide heat transfer between the inlet and outlet to and from the cooling chamber 2 and is also designed so as to require a minimum of insulation. The inlet air from the fan is separated from the cold air leaving the cooling zone 2 by heat conducting walls, which are preferably of metal. In this way the air being supplied to the cooling zone is cooled down by indirect heat exchange with the air leaving this zone. At the point wher the temperature of the exit air approaches or exceeds the temperature of the inlet air, which will be shortly after contact with the heating coil 1, heat exchange is prevented by using separate walls for the two ducts, and heat insulating material 9 may advantageously be placed between the ducts. In actual practice the air ducts will completely surround the brine tank, so as to prevent flow of heat to it from the atmosphere. This design is embodied in the air treating units illustrated in Figures 3 and 4.

It is also desirable to provide suitable means for precipitating any entrained droplets of water from the air leaving the cooling zone 2. Suitable means may provide a quick change in direction of the air stream by baffles 22. These baflies may also be arranged in spiral form to give the air a rotating flow and to precipitate the entrained moisture by centrifugal action.

The hood 29 illustrated in Figure 2 is designed to supply air directly to practically the entire surface of the hair to be dried, the inlet air being directed by vanes 30, and withdrawn by return duct ill at such low pressure that a small amount of atmospheric air is drawn in at the edge of the hood 3|.

It is also generally desirable in devices using recirculation of air from the hood to provide a filter for removing any solid material which may be entrained in the air leaving the hood. This is particularly desirable when employing a single air treating and circulating system for serving a plurality of hoods. Such a filter is illustrated diagrammatically at 23 in Figure 2, and mav consist of any of the usual commercial types of gas filters. provided that the filter does not release any chemical agents which could in any way be deleterious to the human hair.

It is generally desirable in a large system supplying a plurality of units to use two blowers in order to reduce the pressure drop and reduce the load that each blower is required to carry. For example, blowers 32 and 33 are shown in Fig e 2 connected respectively to the inlet and the outlet of the refrigeration unit.

The by-pass 2| from blower 32, and air from the blower 33, discharge into the common air duct 34, which is used for supplying air to a plurality of hoods. The ducts leading to the individual hoods and the return ducts from these hoods are preferably supplied with individual control valves or vanes 35. These vanes are used to regulate the quantity of air to the individual hood. The vanes in the ducts to any one hood will, of course, be closed when that hood is out of service. The two vanes in the ducts leading to and from the same hood are preferably connected together in some suitable manner, so that a balanc between the air entering and leavingthat hood will be effected at any rate of flow. This balance desirably will provide for the return of a slightly greater amount of air than is supplied by the duct leading to that hood, thereby maintaining the desired slightly subatmospheric pressure in the hood, the excess air drawn in being released through the vent ii.

Provision will, of course, be made to care for the increased volume of the returning air due to its decreased pressure. The vanes 35 will be adjusted to maintain this condition in all hoods in use. The hoods will be used in such a manner that the head or hair of the subject does not unduly obstruct either the air supply or air withdrawal passages.

The heat balance, particularly in the multiple unit system, may also require additional control features in order to permit optimum conditions of operation. For example, the temperature of air to the common supply duct may suitably be the lowest temperature considered comfortable by any subject. Additional heat may be supplied to raise the temperature in any individual hood by heating element 8, according to the preferences of the'subject using that hood. This extra heat thus supplied to the system must, of course, be removed by some suitabl means. The heat transferred to the chilled air from the heat dissipating coil 1 of the refrigerating cycle will generally be less than that removed by the refrigeration coil l5 in the brine tank 3, in order to remove the extra heat supplied by the supplemental heating elements. The heat that must be dissipated by the refrigeration cycle may be released to the atmosphere by an additional coil 36 before the refrigerant reaches the expansion valve N. This coil will generally be of sufliciently large capacity to take care of any fluctuations that may occur in the operation of th coil 1 whether due to heat from supplemental heating elements or an accumulation of heat within the cycle from any other source.

Additional control features providing for increased flexibility of operation are the by-pass 31, operated by valve or vane 38, and the by-pass 39, similarly operated by a valve or vane. In the event that the temperature rises to a higher point than desired in supply duct 34, this may be lowered by opening valve'38, thus passing cool air through the by-pass 31. This causes additional heat to be carried by the refrigerant from coil -1 to coil 35, and serves as a means of removing heat from the system. The opposite eflect may be gained and the temperature raised in duct 34 by opening the by-pass 39 and passing additional air over the heating coil 1. This withdraws additional heat from coil 1, preventing its dissipation from the system at coil 35. Valves "and 33 may be operated automatically by a suitable thermostat 45- placed in duct N. If it is found that an additional supply of heat is still required, this may be provided by means of a heating element 40 in the common supply duct 34. This heating element may also conveniently be controlled automatically by a thermostat placed near the outlet of duct 34.

Figures 3 and 4 present illustrative designs of air treating units which may be used in either of the diagrammatic flow plans illustrated in Figures 1 and 2. Air is supplied through duct 5| and is passed through cooling tubes 52 in Figure 3, or 10 in Figure 4 placed in a brine tank 53. The chilled air passes into header 54, and condensed moisture is withdrawn by line 55 and through trap 56. A similar drain for moisture removal 65 is connected to the lower end of the air supply duct 5| in order to remove any moisture collecting at this point. It will be observed that the air supply duct completely jackets the outer wall of the brine tank, thereby preventing transfer of heat from the atmosphere. The chilled air then passes over baflles 52 where entrained moisture is thrown out, then through the outer annular jacket 63 over coils 51 through which is passed the hot compressed refrigerant. The heated air is then withdrawn by duct 54, which is connected either to ducts leading to the hoods as in Figure l, or to the suction side of a fan as in Figure 2. The brine is cooled by expansion coil 68 which is provided with an expansion valve 66. Suitable bailles 61 may be provided to direct the convectional flow of the brine so that it passes along the chilling tubes countercurrent to the air therein. The baflle also prevents direct contact of the expansion coil with the tubes and thus prevents the formation of local excessively cold spots which might cause ice formation. Thermal insulation BI is provided between inlet and outlet air ducts at points where the temperature of the outlet air. exceeds that of the inlet air.

The apparatus illustrated in Figure 3 is designed preferably for operation at temperatures at which there is no danger of ice formation in the air tubes. The temperature of the brine can be controlled by having a thermostat placed therein which is used automatically to regulate the compressor or otherwise regulate the rate at which refrigeration is supplied by the system of which the expansion coil 68 is a part.

The tubes 52 are shown in greater detail in Figures 5 and 6. These tubes are preferably provided with some means for greatly extending the surface to provide increased area for heat transfer. This may be done by suitable fins, corrugations, and the like, on both inner and router surfaces. The packing 69 illustrated serves the dual function of providing both increased internal surface for heat transfer and also promotes turbulent flow of air, thus decreasing air film thickness and increasing the rate of heat transfer. This packing 69 is conveniently manufactured by cutting, as illustrated, the edges of a metal ribbon having a width of approximately the internal diameter of tube 52. The serrated strip is then twisted to form a spiral baiile having projecting elements which make a tight contact with the inner wall of the tube 52.

The apparatus illustrated in Figure 4 is designed for operation under conditions at which ice formation in the air cooling elements may be permitted. While only one of such elements 10 is shown in Figure 4, a plurality of such elements may also be used in parallel or series. These elements are illustrated in detail in Figures 7 and 8. The incoming air passes into a perforated cone or conical section II having an open upper end and a closed lower end. The cone II is disposed concentrically within a cylinder 1! having a corrugated surface, the corrugations or ridges 13 extending inwardly, and the inner surface of each ridge being parallel to a plane tangential to the cone II at the nearest line adjacent thereto. The perforations 14 are aligned longitudinally opposite the ridges in the corrugated cylinders. Brine circulates freely in the depressions in the outer surface of the corrugated cylinders, and thus cools the entire surface. When operating with surfaces at a temperature below the freezing point of water, the air impinging on the ridge 13 may be cooled to the point at which it deposits ice or frost, which collects in the depressions 15. This tends to decrease the eifective surface for cooling, and in so doing, reduces the heat transfer to a point at which ice is no longer deposited. Under such conditions a free passage 16 is left open for the fiow of chilled air and condensed moisture out of the cooling element.

The conical shape of the air tube 1| permits an approximately even pressure on all of the perforations within its surface, so as to permit an approximately uniform fiow of air impinging upon the nearest part of each corrugation throughout its length. Similarly, the depressions in the surrounding cylinder become deeper nearer the bottom, to provide increased space for the greater amount of ice near the bottom as well as insuring sufllcient space for the passage of air with this arrangement. It will be understood that the apparatus shown in the drawings is illustrative, and that thesize and shape of the corrugations, the distance between the cone and the nearest edges of such corrugations, and the size and spacing of air jets may be varied widely to provide satisfactory operation without clogging due to ice over a wide range of air and brine temperatures. The principle of limiting the heat transfer by the formation of ice on the transfer surfaces, with adequate provision for space to contain such ice or frost, is not necessarily confined to the design illustrated, but may be effectively used with other designs accomplishing the chilling of air without clogging due to frost.

This invention is not to be limited to any of the specific examples or drawings presented above, all of these being presented solely for purpose of illustrations, but is limited only by the following claims, in which it is my intention to claim all novelty insofar as the prior art permits:

I claim:

1. A hair drying apparatus of the class described comprising a hood adapted to confine the head, a tank containing a liquid having a freezing point below 32 F.. refrigeration means comprising an expansion coil and a condenser, said expansion coil being located in said tank; a blower, and a duct connected with the output side of said blower and with said hood; said duct passing through the tank in heat exchange relationship with the liquid confined therein; said condenser being located in the duct between the tank and the hood; 9. second duct connected to the hood and the intake side of said blower for recirculating the air; a by-pass connected at one end to said first duct between the blower and the tank, and at its other end to the duct between said tank and said hood; and damper means within said by-pass for regulating the quantity of air recirculated through said tank.

2. A hair drying apparatus of' the class described comprising a hood adapted to confine the head, refrigeration means comprising a heat absorbing anda heat discharge means, a blower and a duct connected with the output side of said blower and with said hood; means for passing the air through said duct first in heat exchange rela-- tionship with the said heat absorbing means and then with the said heat discharge means; a second duct connected to the hood and to the intake side of said blower for recirculating air; a by-pass connected at one end to said first duct between the blower and said heat absorbing means, and at its other end to the duct between said heat absorbing means and said hood, and damper means in said by-pass for regulating the flow of air in heat exchange relationship with said heat absorbing and said heat discharge means.

3. A hair drying apparatus of the class described comprising a hood adapted to confine the head, refrigeration means comprising a heat absorbing means and a heat discharge means, a blower and a duct connected with the output side of said blower and said hood; means for passing the air through said duct first in heat exchange relationship with the said heat absorbing means and then with the said heat discharge means; a second duct connected to the hood and to the intake side of said blower for recirculating air; a by-pass connected at one end to said first duct between the blower and said heat absorbing means, and at its other end to the duct between said heat absorbing means and said hood; another by-pass connected at one end to said first duct between said heat absorbing means and said heat discharge means, and at its other end to a the duct between said heat discharge means and said hood; and damper means in said by-passes for regulating the fiow of air in heat exchange relationship with said heat absorbing and said heat discharge means.

4; A heat exchange apparatus comprising a tank adapted to confine a liquid, a cooling coil disposed in said tank, a jacket around said tank adapted to convey air in heat exchange relationship with said tanks; a second jacket around said first jacket; means for connecting the said first jacket with the said second jacket to convey the said air thereto after said heat exchange, and heating means in said second Jacket adapted to reheat said cooled air, the said apparatus being adapted to dehydrate the said air by condensation of moisture therefrom.

5. A heat exchange apparatus comprising the heat absorbing coil and heat discharge means of a refrigerating system, a jacket around said heat absorbing coil adapted to convey air in heat-exchange relationship with said heat absorbing coil, a second jacket around said first jacket; means for connecting the said first jacket with said second jacket to convey the said air thereto after said heat exchange, the said heat discharge means being in heat exchange relationship with the air in said second jacket and being arranged to reheat said air, the said apparatus being adapted to dehydrate the said air by condensation of moisture therefrom.

6. A heat exchange apparatus comprising the heat absorbing coil and heat discharge means of a refrigerating system, a jacket around said heat absorbing coil adapted to convey air in heat exchange relationship with said heat absorbing coil, 9. bafiie in the said jacket arranged to reverse the flow of air in said jacket; a second jacket around said first jacket; means for connecting the said first jacket with said second jacket to convey the said air thereto after said heat exchange, the said heat discharge means being in heat exchange relationship with the air in said second jacket and being arranged to reheat said air, the said apparatus being adapted to dehydrate the said air by condensation of moisture therefrom.

'7. An air cooling apparatus comprising a refrigeration means, a confined liquid having a freezing point below 32 F. cooled by said refrigeration means, an air duct in contact with said liquid, alternate longitudinal ridges and depressions in the surface of said air duct, means for passing a flow of air through said duct, and means for directing the flow of air in a direction substantially perpendicular to and against said ridges.

8. An air-cooling apparatus comprising a refrigeration means, an air duct in heat exchange relationship with said refrigeration means, al-

ternate projections and depressionsain the surface of said air duct, and means for directing a flow of air with substantially uniform velocity in a direction substantially perpendicular to and against all of said projections.

9. An air cooling apparatus comprising a refrigeration means, an air duct in heat exchange relationship with said refrigeration means, means for causing a flow of air through said air duct, depressions in the surface of said air duct facing the said flow of air, said depressions adapted to receive the formation of ice due to the refrigeration of moisture condensed from said air; and means for directing the said flow of air against the areas between said depressions, adapted to confine the formation of ice to the depressions provided therefor.

10. A hair drying apparatus comprising a hood adapted to enclose a portion of the head of a person; an air conducting means connected at both ends with said hood and arranged to pass air through the hood and over the hair on the head of the person; a condenser and a heater in heat exchange relationship with said air conducting means; a blower connected with said air conducting means to force air therethrough; a by-pass around said condenser; and damper means in said by-pass for regulating the flow of air in heat exchange relationship with said condenser and heater.

11. A hair drying apparatus comprising a hood adapted to enclose a portion of the head of a person; an air conducting means connected at both ends with said hood and arranged to pass air through the hood and over the hair on the head of the person; a condenser and a heater in heat exchange relationship with said air conductin means; a blower connected with said air conducting means to force air therethrough; a by-pass around said heater; and damper means in said bypass for regulating theflow of air in heat exchange relationship with said condenser and heater.

CHARLES ALBERT PHIPPS. 

